Tractors and other earthmoving vehicles equipped with implements and associated controls mounted both to the front and to the rear of the operator's compartment or platform are well-known in the art. For example, U.S. Pat. No. 4,081,051 to John S. Logsdon, issued Mar. 28, 1978 and assigned to the assignee of the present invention discloses a track-type vehicle having an implement such as a backhoe mounted behind the operator's platform. A dual control arrangement is also shown with one of the controls mounted to the front of the operator's compartment for steering the tractor or for operating the forwardly located implement, and with the other of the controls mounted to the rear of the operator's compartment for operating the backhoe.
The location of the backhoe controls, being higher above the operator's platform than the front mounted controls, is such that for the operator to run the backhoe efficiently, he must be able to sit facing it in a position which is elevated with respect to the forward operating position. To this end, there is provided a seat with a back mounted for movement between positions at opposite transverse margins of the seat. The seat is mounted upon an adjustable carriage, having a front portion supported on rollers in a pair of parallel channels or tracks and a rear portion carried by a pair of supporting links. A manual lever is operatively connected to the carriage so that it can swing the rear of the carriage upwardly and rearwardly by pivoting it on the supporting links. At the same time the rollers at the front of the carriage move rearwardly in the tracks.
However, the seats of the prior art do not fully satisfy the requirements for an adjustable and reversible seat. The manufacturing tolerances of the links, slides, and rollers forming the adjustable carriage are such that after assembly, an undesirable amount of movement or "play" is introduced into the carriage. This "play" in the carriage translates into an undesirable and annoying amount of movement of the seat, particularly in the rearward, elevated position, which interferes with efficient operation of the vehicle. Further, this condition is aggravated over a period of time as repeated use and movement of the seat wears and thereby loosens the carriage.
The foregoing illustrates limitations of the known prior art. Thus, it is apparent that it would be advantageous to provide an alternative to the prior art.